1. Field of the Invention
Technology described herein relates to deposition of thin films using microwave deposition.
2. Description of the Related Art
Silicon-containing films are used for a wide variety of applications in the semiconductor industry. Silicon-containing films include silicon films such as silicon oxide (SiO)x), polycrystalline silicon (poly-Si) and epitaxial silicon, microcrystalline silicon (μc-Si), amorphous silicon (a-Si), silicon germanium (SiGe), silicon germanium carbide (SiGeC), silicon carbide (SiC), silicon nitride (SiN), silicon carbonitride (SiCN), and silicon carboxide (SiCO). The silicon-containing films may be formed by a plasma process.
In general, plasma processing involves positioning a substrate on a support member (often referred to as a susceptor or heater) disposed in a vacuum chamber and forming a plasma adjacent to the upper exposed surface of the substrate. The plasma is formed by introducing one or more process gases into the chamber and exciting the gases with an electrical field to cause dissociation of the gases into charged and neutral particles. A plasma may be produced inductively, e.g., using an inductive RF coil, and/or capacitively, e.g., using parallel plate electrodes, or by using microwave energy.
Many plasma processes employ capacitance coupled plasma (CCP) for the formation of the activated species to deposit on the substrate. However, the explosive behavior of SiH4 and corrosive behavior of SiF4 requires strict control over processing conditions and careful handling of the process effluent. Furthermore, deposition of SiOx films from SiF4 require high deposition temperatures that are incompatible with advanced device processing requiring a low thermal budget.
Thus, methods are needed that can provide lower temperature deposition of thin films with higher deposition rates and lower defect rates.